From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 55D831494C4 for ; Thu, 15 Aug 2024 05:24:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723699469; cv=none; b=AyGuhUmn9xzmKS3K/122kY0Arfz8OSjxxqn2wYFhxn+LuqB0j9K/U+TuWMsBya0/vY/sLjmyle2lXhtCnH0FFp/+OpGVQpR71DBfeeHP1YcJ20nucrz/JHNrYhssjWXEsokaXqHusMhD7hk9mBRKejPOLZ+QxBhTpp+3KLJ7c8s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723699469; c=relaxed/simple; bh=kjXfPq9BkqNLiNmkWUNGgnT0PMeMF1lcxBd3MEdFQrA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ip9JXye+0kX5BNrw1a3Db4dw2wakHTYCn6q5nKQ40VkvAJjc6NhpSGDBBHIgrA/Fyrs+hlmElZt9TIErroCK5/pIUPR7k50IYl6XrFS3SRayl+Yod9RRl+H/pwFuWgY7P1HPnhgSGMkV7e95WUlNzxDmfTXVfFAgxuB6XK0Q85s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=WQiqFCCc; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="WQiqFCCc" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1723699466; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=UYx7xZkt9eSbJOCYSPXaKHYVyo+CtQM88si3lp0YJtw=; b=WQiqFCCcYkzcsu9GTiQIfs5sPyeIWOERTtSFPzA+8B1Yx/ro/bl9RbZ3HWbZnldaErEkgX RAuNuoobx3YmiZ4Ih0HwpPg9F3iidZ9YUCEVQYj/OJKWG7mRVumUQCHm73LjkSZ0HS2FdT SnJG7IoerEk9zz5+ENc3fljKuHWElVg= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-624-_ltXWiIJMva5k6Y2aAdKBA-1; Thu, 15 Aug 2024 01:24:17 -0400 X-MC-Unique: _ltXWiIJMva5k6Y2aAdKBA-1 Received: from mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.40]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id CD82C195609E; Thu, 15 Aug 2024 05:24:15 +0000 (UTC) Received: from localhost (unknown [10.43.135.229]) by mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 2D38119560A3; Thu, 15 Aug 2024 05:24:12 +0000 (UTC) Date: Thu, 15 Aug 2024 07:24:10 +0200 From: Miroslav Lichvar To: Richard Cochran Cc: Andrew Lunn , Vadim Fedorenko , Maciek Machnikowski , netdev@vger.kernel.org, jacob.e.keller@intel.com, darinzon@amazon.com, kuba@kernel.org Subject: Re: [RFC 0/3] ptp: Add esterror support Message-ID: References: <20240813125602.155827-1-maciek@machnikowski.net> <4c2e99b4-b19e-41f5-a048-3bcc8c33a51c@lunn.ch> <4fb35444-3508-4f77-9c66-22acf808b93c@linux.dev> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 3.0 on 10.30.177.40 On Wed, Aug 14, 2024 at 09:16:12PM -0700, Richard Cochran wrote: > Actually, looking at the NTP code, we have: > > void process_adjtimex_modes(const struct __kernel_timex *txc,) > { > ... > if (txc->modes & ADJ_ESTERROR) > time_esterror = txc->esterror; > ... > } > > So I guess PHCs should also support setting this from user space? Yes, I'd like that very much. It would allow other applications to get the estimated error of the clock they are using. Maxerror would be nice too, even if it didn't increase automatically at 500 ppm as the system clock. IIRC this was proposed before for the cross-timestamping PHC between VM host and guests, but there wasn't much interest at the time. -- Miroslav Lichvar